Disclosed herein is a joint unit including two facing gears that include respective two bevel gear members that face each other, and an intermediate gear that has a bevel gear member meshing with both the two bevel gear members. One of the two facing gears and the intermediate gear includes a first member including an inner circumferential portion of the bevel gear member of the one of the two facing gears and the intermediate gear; a second member including an outer circumferential portion of the bevel gear member of the one of the two facing gears and the intermediate gear; and a resilient member attached to one of the first member and the second member for normally urging the other of the first member and the second member to move in a direction along the directions of rotation of the one of the two facing gears and the intermediate gear.

A work of incorporating a speed reduction mechanism including a scissors gear into a gear case is facilitated. In a state where the angular positions of gear teeth of a first gear and the angular positions of gear teeth of a scissors gear are made to coincide with each other against the elastic force of a torsion spring (19), these angular positions are fixed by a fixing member (position fixing step). The first gear, the scissors gear, and a second gear are housed in a gear case, and the gear teeth of the second gear are made to engage with the gear teeth of the first gear and the gear teeth of the scissors gear (gear incorporating step). The fixing of the angular position of the first gear and the angular position of the scissors gear by the fixing member is released through an opening formed in the gear case.

A work of incorporating a speed reduction mechanism including a scissors gear into a gear case is facilitated. In a state where the angular positions of gear teeth of a first gear and the angular positions of gear teeth of a scissors gear are made to coincide with each other against the elastic force of a torsion spring (19), these angular positions are fixed by a fixing member (position fixing step). The first gear, the scissors gear, and a second gear are housed in a gear case, and the gear teeth of the second gear are made to engage with the gear teeth of the first gear and the gear teeth of the scissors gear (gear incorporating step). The fixing of the angular position of the first gear and the angular position of the scissors gear by the fixing member is released through an opening formed in the gear case.

A drive gear assembly rotatably drives a driven gear of an engine component. The drive gear assembly comprises a drive shaft extending longitudinally along an axis. A main drive gear is operatively coupled to the drive shaft and a scissor gear is aligned coaxially with the main drive gear. A scissor spring is disposed and operatively coupled between the main drive gear and the scissor gear and biased therebetween wherein the main drive gear and the scissor gear rotate about the axis relative to each other. An isolation mechanism is operatively coupled between the main drive gear and the drive shaft for absorbing impulse loads generated by the driven gear when engaged with the main drive gear.

A drive gear assembly rotatably drives a driven gear of an engine component. The drive gear assembly comprises a drive shaft extending longitudinally along an axis. A main drive gear is operatively coupled to the drive shaft and a scissor gear is aligned coaxially with the main drive gear. A scissor spring is disposed and operatively coupled between the main drive gear and the scissor gear and biased therebetween wherein the main drive gear and the scissor gear rotate about the axis relative to each other. An isolation mechanism is operatively coupled between the main drive gear and the drive shaft for absorbing impulse loads generated by the driven gear when engaged with the main drive gear.

An opposed-piston engine includes a backlash reducing gear with at least a first and second gear that move relative to each other because of a hydraulic pressure applied within the gear. A backlash control system that includes the backlash reducing gear can dynamically adjust backlash between at least two gears in the gear train of the engine during operation of the engine instead of setting backlash prior to operation of the engine. A method for adjusting backlash in a two-stroke-cycle, opposed-piston engine with a backlash reducing gear includes providing hydraulic fluid, such as oil, to the gear, and allowing the backlash reducing gear to adapt to changes in the engine that include temperature changes, torque reversals, changes in load and the like. The backlash reducing gear adapts to changes in the engine by controlled leaking and intake of oil.

A gear drive (12) with a first gear (10) which has first tooth flanks (26), and a second gear (30) which has second tooth flanks (32) and which engages with the first gear (10), the first gear (10) having a tip circle (14) with a tip circle radius (16), a root circle (18) with a root circle radius (20) and a modification circle (22) with a modification circle radius arranged between the tip circle (14) and the root circle (18). (24), wherein the first tooth flanks (26) between the root circle (18) and the modification circle (22) each have a recess (28) in such a way that, when the gears (10, 30) mesh, there is no contact between the first tooth flanks (26) and the second tooth flanks (32) between the root circle (18) and the modification circle (22), and a longitudinal seat adjustment for a motor vehicle with a gear drive (12).

A gear device includes a housing, a cover, and a positioning portion. The cover includes a first bearing that receives a first shaft and a second bearing that receives a second shaft. The positioning portion includes a projection that projects from one of the housing or the cover parallel to the first shaft or the second shaft and a fitting hole that is formed in the other one of the housing or the cover to receive the projection. The projection has a length that is set so that when coupling the cover to the housing, in a state in which the first shaft is inserted through the first bearing, the projection enters the fitting hole before the distal end of the second shaft enters the second bearing.

A gear device includes a housing, a cover, and a positioning portion. The cover includes a first bearing that receives a first shaft and a second bearing that receives a second shaft. The positioning portion includes a projection that projects from one of the housing or the cover parallel to the first shaft or the second shaft and a fitting hole that is formed in the other one of the housing or the cover to receive the projection. The projection has a length that is set so that when coupling the cover to the housing, in a state in which the first shaft is inserted through the first bearing, the projection enters the fitting hole before the distal end of the second shaft enters the second bearing.

A scissor gear assembly 1 has a main gear 3 and auxiliary gear 5 concentric to the main gear and in axial direction near the main gear. Further the assembly has a planar annular spring 7 being interrupted at one place. At the interruption the spring has two ends 7A and 7B. The spring is present between both gears and is with one end 7A connected to the main gear 3 and with the other end 7B to the auxiliary gear 5, so that both gears are connected to each other in rotation direction via the spring. Each end 7A, 7B of the spring is provided with an extension 9 forming extra mass. These extensions are each provided with a slot 13. Because of these extra masses the spring torque will vary depending on the rotational speed of the gear assembly.